I thought Dolby Vision was equivalent to HDR10+, not basic HDR10.
This is because Dolby Vision has addition of dynamic metadata to the core HDR image data.
With HDR10 content, the tV only gets static metadata; relatively basic ‘global’ information on the content being shown that applies to the entire film or TV show.
HDR10+ or Dolby Vision sends meta data scene by scene so is far more accurate.